Birds sing beautiful songs in the sky.
Meaning: It means birds make sounds with their mouths that are pleasing to the senses or mind aesthetically in the area of the atmosphere and outer space that you can see when you look up from Earth.
Choice of Words: Birds are warm-blooded vertebrates constituting the class Aves, characterized by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight skeleton. Sing means to produce musical sounds with the voice. Beautiful means pleasing the senses or mind aesthetically. Songs are musical compositions consisting of vocal or instrumental sounds (or both) with lyrics. Sky is the region of the atmosphere and outer space seen from the Earth's surface. When you put them together, the sentence is saying that warm-blooded vertebrates constituting the class Aves, characterized by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight skeleton produce musical sounds with their voices that are pleasing to the senses or mind aesthetically in the region of the atmosphere and outer space seen from the Earth's surface.
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